


Someday

by LunarHermit



Series: Everything Stays (Everything Changes) [5]
Category: Fire Emblem Series, Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: F/F, Female My Unit | Byleth, Ferdinand and Dorothea had a kid for my convenience, Fluff, I've been assured this is pure fluff, Post-Game, Silver Snow Route, his name is Edgar von Aegir
Language: English
Status: Completed
Published: 2020-04-21
Updated: 2020-04-21
Packaged: 2021-03-02 00:06:53
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,525
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23765848
Author URL: https://archiveofourown.org/users/LunarHermit/pseuds/LunarHermit
Summary: For just a moment, instead of Ferdinand and Dorothea’s orange-haired son, Byleth saw a little girl.A little girl with mint green hair and sparkling green eyes, her smile brighter than the stars in the sky as she giggled and held a little green frog in the palm of her tiny hand.Byleth blinked and the vision before her wavered and dissipated, rolling away like the morning fog, and she was once again looking at a giggling mud-covered boy.
Relationships: My Unit | Byleth/Rhea
Series: Everything Stays (Everything Changes) [5]
Series URL: https://archiveofourown.org/series/1563757
Comments: 22
Kudos: 61





	Someday

**Author's Note:**

> I needed a kid, and so Ferdinand and Dorothea had a son. I'm not sorry. 
> 
> I've also been assured that this story is pure fluff and quite adorable. I'm not sorry about that either.

**-+-+-**

“Look, Auntie!” Edgar exclaimed, excitement shining in the dark green eyes peeking out from beneath messy orange bangs. “It’s a froggy!”

Byleth tilted her head slightly, her gaze scanning the ground at Edgar’s feet. As if sensing her trouble, the little boy crouched down and pointed, his finger barely brushing a small green body before it hopped forward, startling a laugh out of him.

“Yes, I can see that.” Byleth nodded, a faint smile tugging at her lips.

The boy burst into giggles as the little green frog ribbitted and jumped again.

“We have froggies at my home too,” Edgar said once his giggles were under control as he followed the frog’s progress with his eyes. “But my ones are big and brown.”

He looked up at Byleth and explained helpfully, “There’s a bunch of them, and they hop and play together, except when it gets too cold. Father says that’s when the froggies sleep until it gets warm again.”

“Hmm,” Byleth hummed, as if suddenly everything made sense. “I suppose that means that it’s warm enough to play.”

“Uh-huh!” Edgar nodded in agreement before a troubling thought suddenly occurred to him. His bright smile turned into a small frown as his gaze dropped, and he began intently scanning the ground.

“What’s wrong?” Byleth asked, concerned at the boy’s sudden frown.

“Auntie,” Edgar said as he finished his scan, his dark green eyes raising to meet her lighter ones. There was a worried pout on his face. “It’s time to play, but there’s only one froggy! Where are all his friends?”

“Ah,” Byleth blinked, her eyes instinctively scanning the ground only to come up empty as well. A flash of sunlight on water out of the corner of her eye caught her attention, however, giving her an idea. “Perhaps they’re at the lake?”

“Oh! That makes sense. Froggies love water.” Edgar said, before pointing out with a troubled little frown, “But this little froggy is so far away from the lake! If he doesn’t hurry, he won’t be able to play with his friends before his mother froggy tells him it’s time for bed.”

Raising a brow at the young boy’s concerns, Byleth nevertheless nodded. “I suppose you’re right. What do you suggest we do, then?”

Edgar hummed in thought for a long moment before a blinding smile erupted across his face. Puffing out his small chest, he switched his smile out for a profoundly serious expression and pointed enthusiastically at the frog. “Don’t worry little froggy! I, Edgar von Aegir, will protect you and lead you to your friends!”

Almost as an afterthought, he added, “Auntie will help too!” He turned to the woman in question innocently. “You will, won’t you Auntie?”

“Of course,” Byleth nodded seriously, accepting the mission of great import with the gravitas it deserved.

The two of them arranged themselves behind the frog and began slowly herding it towards the lake. For a long while, the only sound besides the faint rustling of the wind through the leaves and grass was the occasional ribbit from their little green charge.

“I wonder if it’s a girl froggy or a boy froggy,” Edgar piped up suddenly. “Do you know, Auntie?”

“No,” Byleth shook her head.

“Oh,” Edgar pouted, before his eyes brightened. “Oh! I know! Mother told me a story about a prince that was cursed by a witch and turned into a froggy because he was being mean. He had to be kissed by a princess before he could turn into a prince again. Maybe if we get a princess to kiss the froggy, we’ll see if he turns into a prince too, and that would mean he’s a boy froggy.”

“But we don’t have any princesses with us,” Byleth pointed out reasonably.

“You’re right.” Edgar frowned, before suddenly exclaiming in excitement, “But wait! You’re a _queen_ , Auntie! Queens are even _better_ than princesses. I’m sure if _you_ kiss the froggy, it’ll turn into a prince or a princess and then we’ll know for sure!”

“Ah…” Byleth blinked, nonplussed at the conclusion the young boy had suddenly come to. She took in Edgar’s eager expression, his grin wide and innocent. She was loath to ruin the little one’s obvious joy, however…

She really did not want to kiss the frog hopping obliviously around their feet.

In the face of such innocent excitement, Byleth said the first thing that came to mind. “I don’t think Rhea would be too happy if I started kissing frogs…”

“Huh. I didn’t think about that,” Edgar said, voice thoughtful.

Byleth was momentarily concerned that she had put a damper on the young boy’s joy, only for her worries to be assuaged as instead of breaking into tears, Edgar instead nodded.

“I guess that makes sense.” Edgar nodded sagely, before looking at the frog and explaining apologetically, “I’m sorry froggy, but Auntie Poffessor’s kisses are only for Auntie Rhea, or else Auntie Rhea might get sad. You’ll just have to wait for a prince or a princess to come play with you.”

A sudden thought occurred to the little boy, and he turned his wide-eyed gaze back on the subtly relieved woman beside him. “But wait! If you’re a queen, doesn’t that mean if you have a baby it’ll be a prince or a princess? Then your _baby_ can kiss the froggy!”

“I…” Byleth hesitated, before slowly continuing, “I suppose _technically_ …”

“Don’t worry froggy!” Edgar grinned back down at the frog. “Auntie Poffessor and Auntie Rhea love each other lots, and Mother said that only grownups who love each other lots have babies, so I’m sure if I let Auntie Rhea know that you’re waiting for a prince or princess she won’t mind having a baby with Auntie Poffessor.”

Byleth could only open and close her mouth, speechless, as she was once more blindsided by the young boy’s innocent logic. In the face of those expectantly hopeful eyes, however, Byleth could do nothing but sigh and nod with a slight smile. The blinding grin she received in return, she felt, was well worth her silence on the matter.

It took the two of them nearly an hour to herd the frog most of the way to the lake, though it wasn’t because the lake was particularly far away – it was in fact just visible from the back of the house Byleth had built on the outskirts of Zanado – but because the frog kept hiding in the tall grass before jumping in the wrong direction. Edgar’s joy in their task was evident, however, and so Byleth simply continued to use her feet to gently nudge the frog whenever it hopped too far off track.

Suddenly noting the dark clouds swiftly rolling in, and the distance still left to the lakeshore, Byleth frowned. If they did not pick up the pace, they were sure to be caught out in the rain when the sky finally opened up. “Perhaps we should pick up the frog and bring it the rest of the way?”

“Uh-uh,” Edgar shook his head. “We can’t do that.”

“Oh?” Byleth’s brow rose in question. “Why not?”

“Mother says that just because someone is bigger or stronger or luckier or has more money than somebody else, doesn’t mean they’re not cap- cape- capable of doing things themselves, and that it’s pretenshoes to think that way.” Edgar explained carefully, though he still stumbled over the large words. “We can help the froggy by showing him the way, but we can’t be _pretenshoes_ , Auntie. That would be mean.”

“You’re right of course, Edgar. Being pretentious would be mean.” Byleth eyed the clouds once more before sighing. “But maybe we can ask the frog to hop a little faster?”

“Okay,” Edgar nodded in agreement. “I’ll cheer him on so that he works harder. I always work harder when Mother and Father cheer me on.”

They eventually made it to the water’s edge without incident, though Byleth continued to eye the sky every couple of minutes in mounting worry. Her latest glance coincided with a splash and a giggle, and Byleth’s head jerked down just in time to see Edgar sit up from where he had fallen in a puddle, a toothy smile on his face.

Byleth blinked slowly as she silently watched the young boy giggle in the mud, a group of tiny green frogs jumping around him playfully. The darkening sky wasn’t solely due to the rainclouds rolling in, and Edgar would definitely require a bath before bed – not to mention the absolute mess the mud would surely make as they trekked through the house no matter how careful they were.

And yet.

And yet, despite the exhaustion she had signed herself up for by babysitting during what was supposed to be a weekend in Zanado to relax from her royal duties, Byleth couldn’t help but simply gaze indulgently at Edgar as she let her mind wander. Slowly, an image began to take shape without her conscious thought.

For just a moment, instead of Ferdinand and Dorothea’s orange-haired son, Byleth saw a little girl.

A little girl with mint green hair and sparkling green eyes, her smile brighter than the stars in the sky as she giggled and held a little green frog in the palm of her tiny hand.

Byleth blinked and the vision before her wavered and dissipated, rolling away like the morning fog, and she was once again looking at a giggling mud-covered boy.

Emotions suddenly in turmoil, Byleth turned to gaze out over the water, an altogether pensive expression slowly settling across her features.

**-+-+-**

“Well now, you two certainly look like you have been enjoying yourselves,” Rhea noted with a poorly hidden smile as she took in the mud-caked forms, twin puddles of dirty water forming at their feet.

“Auntie Rhea!” Edgar grinned excitedly before slicking his bangs away from his eyes, a trail of mud being left behind in the soaked hair. “We had _so_ much fun! Me and Auntie helped a froggy find his friends, and then I got to play with them!”

“We weren’t sure if it was a boy froggy or a girl froggy though. But don’t worry,” Edgar explained, before reassuring her, “Even though Auntie’s a queen she didn’t kiss the froggy to find out, because she saves her kisses for you so that you won’t be sad.”

“Oh? I am happy to hear that,” Rhea said in gentle amusement, her eyes flicking towards Byleth only for her love to avert her gaze almost shyly. She was delighted to witness a slight flush slowly creep over pale cheeks under her observant gaze. After a moment, Rhea looked back down at Edgar and whispered, as if telling him a grand secret, “I, too, save my kisses for your Auntie. I would never wish to make her sad either.”

Edgar nodded sagely.

“That’s ‘cause you love each other lots and lots, and that’s what I told my new froggy friend,” Edgar explained. “He doesn’t mind though. He can wait until you and Auntie have a prince or princess to kiss him. He’s got lots of froggy friends to play with until then, so he won’t be lonely.”

Rhea’s eyes widened slightly at the child’s words, her gaze once more cutting across to Byleth. No longer simply lightly flushed, the younger woman’s face was now completely red. Slowly, green eyes hesitantly rose to meet her own before Byleth shrugged almost awkwardly, a small rueful smile dancing at the corners of her lips.

Completely charmed, Rhea let out a light tinkling laugh as she focused back on the boy before her.

“Is that so? I am beyond delighted that your frog has such good friends to keep him company,” Rhea assured the grinning boy. “But for now, I believe that it is time that someone get washed up before bed.”

Edgar wrinkled his nose. He looked up and scanned Byleth for a moment, a serious expression sliding across his face, before turning back to Rhea with a firm nod. “I think you’re right, Auntie Rhea. Auntie Poffessor is _really_ messy.”

“While true, she isn’t the only one.” A voice said just before Edgar was picked up, the little boy squealing in shocked joy. “Isn’t she, kid?”

Edgar’s eyes widened excitedly, his smile splitting his face as he giggled and threw his arms around the blond woman now holding him. “Auntie Cat! Did you know there are _green_ froggies here?”

“Are there?” Catherine’s brow rose in mock disbelief as she jostled him purposefully. “Are you sure?”

“Yeah, there’s _lots_!” Edgar grinned as he bounced. “I got to play with them at the lake and it was _so_ much fun!”

“Well, why don’t you tell me all about it while we get you cleaned up, huh?” Catherine suggested before shifting the giggling boy until she was holding him under one arm. She looked up only to suddenly blush as she realized that two sets of green eyes were staring back at her in gentle amusement.

Catherine tried her best to steadfastly ignore the heat on her cheeks as she started the report she had meant to give upon entering the room. “Perimeter’s all clear, Lady Rhea. The Guardian Golems you set up are working as expected and haven’t come across anything either. If they do, we should be alerted well in advance.”

“Thank you, Catherine. Your diligence in the matter of our safety is appreciated, as always.” Rhea smiled genuinely at the usually boisterous blond and watched as blue eyes averted almost bashfully at the praise.

“It’s my pleasure, Lady Rhea. No harm will come to either of you while I’m around,” Catherine swore seriously, before clearing her throat. Turning her gaze to Byleth, an almost teasing grin slid onto her face. “I’ll take care of getting the kid all cleaned up and ready for bed, so that the two of you actually have some time to relax. Might I suggest that you get cleaned up as well, Your Majesty?”

“Catherine,” Byleth sighed as she eyed the grinning blond in mild exasperation. “Please, you know there’s no need for titles between us.”

“She means that you should call her by her name, Auntie Cat,” Edgar piped up helpfully from under her arm. “It’s Auntie Poffessor, if you forgotted.”

“I know what she means, kid,” Catherine jostled the boy playfully. “But I can’t call her Auntie Professor like you do.”

“Why not?” Edgar asked in bewilderment. “That’s her name. Right Auntie? You don’t mind if Auntie Cat calls you by your name?”

“I would prefer my name to my title, yes,” Byleth assured them, a faintly amused smile curling her lips.

“See? _Told_ you Auntie Cat,” Edgar said brightly. “Auntie Poffessor _want_ s you to call her by her name.”

“That’s not-,” Catherine started arguing, only to catch Rhea delicately covering a smile with her hand out of the corner of her eye. Flustered once more, Catherine nodded at the two women before quickly walking in the direction of the guest rooms. She spoke to the boy dangling under her arm, “Let’s just get you cleaned up before _you_ turn into a frog.”

“That can _happen_?!” Edgar gasped in utter amazement.

The two green-haired women shared an amused smile as the young boy’s astonished voice faded away, before Rhea’s eyes softened.

“Well, now that Catherine is seeing to our little guest,” Rhea started as she walked forward, her palm settling momentarily on Byleth’s clean yet damp upper arm before sliding down to brush against a muddied hand. Ignoring Byleth’s half-hearted attempts to pull away, Rhea entwined their fingers, utterly unconcerned by the mud now coating her own. “We should see about getting you cleaned up as well, dear one, before that mud starts to dry and harden.”

Grimacing slightly at that uncomfortable thought, Byleth immediately nodded and toed off her boots. Once they were discarded by the door, she started in the direction of their rooms only to be pulled to a gentle halt by the hand still wrapped around her own. Turning her head, she gazed up at Rhea quizzically.

“But first,” Rhea said as she used their entwined hands to tug Byleth closer, her free hand rising to brush softly against a damp cheek before cupping it. Byleth’s eyes widened slightly, before softening in understanding.

Finding no resistance, Rhea gently tilted the younger woman’s face upwards before leaning in, the tips of their noses brushing together for a few playful moments before a small sound escaped Byleth’s throat. Only then did Rhea dip her head down fully to gently brush their lips together, a soft sigh of happiness escaping her at the contact as her eyes fluttered shut.

Byleth murmured back her agreement, her own eyes closing as she unconsciously pressed closer. Her free hand mirrored Rhea’s as it rose up to cup a soft cheek in a gentle attempt to dissuade the other woman from retreating. She need not have worried, however, as Rhea had no intention of rushing or ending their embrace.

And so, one soft kiss turned into many, until the threat of drying mud became a reality and Byleth could not help but shift slightly in discomfort. It was thus Byleth who eventually broke their kiss, though she did so gradually and with great regret. Green eyes fluttering open, Byleth’s gaze was instantly drawn to the cheek she still cupped.

“I’ve gotten you all muddy,” Byleth murmured as her thumb smoothed against the streak of brown standing out starkly against pale skin, though she only succeeded in smudging it further. The cheek under her hand shifted and tightened as Rhea’s lips curled into a small smile.

“I love you,” Rhea replied simply without even a hint of concern at her newly unkempt state, her voice soft and warm as she gave in to the urge to place just one more kiss against the lips still so close to her own.

“Hmm…” Byleth hummed happily, before finally stepping back. She half-turned in the direction of their rooms, the thought of a hot bath sending a thrill of anticipation through her, and gave a slight tug on the hand entwined with her own.

“Join me?” Byleth asked hopefully.

“Always,” Rhea replied instantly, sincerity shining in light green eyes.

**-+-+-**

Byleth snuggled further into Rhea’s lap, the soothing sensation of a hand gently stroking through her still-damp hair causing her to sigh in contentment. Eyes half-lidded, she turned her head slightly to the side so that she could gaze into the crackling fire before them, the flames dancing hypnotically to and fro. Immeasurably relaxed, Byleth took a moment to simply drift in a bubble of warm serenity, her mind wandering aimlessly.

Eventually, her thoughts drifted to the little boy sleeping in their guest room, and Byleth could not help but reflect on her day. Since she had become used to corralling a class of headstrong and opinionated students with differing views - and each with their own laundry list of odd quirks and mannerisms - she had thought that she knew what she was agreeing to when she’d told Ferdinand and Dorothea that she’d watch their son for a few days. What she had not realized, however, was that being a professor and caretaker to a group of teenagers and young adults was vastly different than watching over a young child.

Children, Byleth ultimately concluded, were terribly exhausting.

While Edgar was not a troublesome child - and was in fact rather well behaved for his age - she had quickly come to note that he possessed a seemingly unlimited font of restless energy. They had spent the entire day outside in an attempt to tire him out, and yet no matter what activity they participated in – be it running around, collecting bugs, training with wooden swords, or herding frogs – he was always full of energy and ready for the next adventure.

Byleth, despite the great stamina afforded to her by the changes brought forth from merging with Sothis, had been more than happy to finally usher the boy towards the house when the rain began to fall.

And that was not even considering the mental exhaustion. Just attempting to keep up with Edgar’s constant excited chatter had been a job in and of itself, and more than once Byleth had contemplated pausing time to give herself a moment to actually digest what the little boy was saying. Not to mention that his leaps in logic continuously left her on the backfoot, which was an odd and unwelcome feeling after being raised to instantly adapt to an ever-changing battlefield.

And yet despite the exhaustion - despite the feelings of inadequacy and unpreparedness - Byleth could not help but think back to that vision at the edge of the lake.

“How did you know?” Byleth asked suddenly into the silent room.

“Hmm…?” Rhea hummed as she tore her eyes away from the book in her hand and looked down at the head in her lap. “What was that, love?”

Byleth shifted just enough that she could peek up at the other woman, momentarily getting lost in the sight of soft inquisitive eyes, the tips of pointed ears just peeking out from between long strands of loose green. The hand in Byleth’s own hair moved to tuck a stubborn strand of green behind her ear, snapping Byleth from her thoughts.

Byleth blinked rapidly, before repeating her question. “How did you know that I’d be a good professor?”

“How did I…” Rhea trailed off, somewhat surprised at the seemingly random topic.

“Mm.” Byleth nodded, before explaining slowly, “I’d never really interacted with people much, so it came as a surprise to both my father and me. I honestly didn’t think that I’d be able to handle it. But you were always so sure of my capabilities, even from the start. How did you know?”

“That is… rather complicated,” Rhea stated delicately with a small thoughtful frown. In the face of Byleth’s openly inquisitive stare, however, Rhea sighed. She trailed her fingers lightly across Byleth’s cheek, before returning her hand to its earlier ministrations.

“At first it was because you were Jeralt’s daughter - the daughter I could not help but dearly hope would turn out to be the child thought lost in the fire those many years ago.” Rhea paused, before finally admitting, “The child carrying my mother’s Crest Stone.”

Byleth simply nodded, figuring it had been something along those lines.

“I had expected you to be competent, fair, and kind – all wonderful attributes to have when one is shaping young minds. And yet despite my high expectations, you continuously not only exceeded them, but did so with seeming ease,” Rhea’s smile turned loving, her finger gently tapping Byleth on the nose before returning to sifting through soft hair. “You surprised even me, dear one, with just how kind and selfless you really were.”

“I truly regret how long it took me to begin seeing you for who you were, and not who I so desperately wished you might be.” Rhea sighed softly. “Every time a kernel of doubt would appear, you would do something extraordinary - your every action simply serving to further cement my view of you. I-,”

Rhea went silent for a long moment before whispering softly, helplessly, her eyes silently pleading with Byleth to believe her. “I see you now.”

Byleth reached up and grasped the hand frozen in her hair, gently tugging it downwards as she entwined their fingers. She softly kissed the skin just above the silver and purple ring before pressing their joined hands above her heart. Her smile was gentle and full of understanding. “I know.”

“I still do not know what I have done to deserve you,” Rhea murmured, her awed gaze drifting between the rings adorning their fingers and the smiling green eyes looking up at her in unguarded acceptance.

“I see you, too,” Byleth replied simply.

“You truly do, don’t you?” Rhea shook her head with a slight smile of disbelief. Clearing her throat after a long moment, she moved back to the previous topic. “What brought about such a question?”

“I was simply thinking about Edgar. He is a sweet child – but so full of energy. I wondered how Dorothea and Ferdinand knew they were ready to be parents, and how they cope with having a small child around constantly,” Byleth idly wondered aloud. “I tried to compare it to having a class full of students, and then wondered why you were always more certain of my capabilities than I.”

“I do not believe that anyone is truly prepared to become a parent.” Rhea spoke after a moment of consideration. “They simply learn as they go, the rewards far outweighing the troubles.”

Byleth hummed before nodding slowly. “I suppose that makes sense.”

The two once more lapsed into comfortable silence. Rhea turned back to the book of poems in her hand, the other still pressed against the warm skin above Byleth’s heart. Though Byleth resumed gazing unseeingly into the flickering flames, she did so not to let her mind wander, but instead while lost in deep thought.

The once tall flames had died down considerably by the time Byleth blinked, having finally come to a decision. She spoke abruptly into the silence, “I think I would like it.”

“Oh?” Rhea glanced away from her book in instant curiosity. “What would you like?”

“Children,” Byleth clarified helpfully, before rolling over until she was gazing up into Rhea’s openly startled face.

“I- I am sorry, I-,” Rhea blinked and stuttered, taken aback at the casually spoken words. She could not help but wonder if she had misheard, and so took a deep breath before clearing her throat and attempting to speak once more. “Would you mind repeating that, dear one?”

“I think I would like to have children.” Byleth repeated guilelessly before adding, “If it was with you.”

Rhea was speechless, and despite opening and closing her mouth several times, could do nothing more than gaze down into sincere green orbs in astonishment.

Byleth’s brow furrowed as the silence stretched on. She worriedly asked, “Did I say something wrong?”

“No,” Rhea blurted out immediately in reassurance, her head shaking though her eyes were still wide. “No, of course not – you did not say anything wrong at all. I was... merely caught off guard.”

Byleth relaxed back into Rhea’s lap at her words, her worried frown once more replaced with curiosity.

“I…” Rhea trailed off into an emotional chuckle. She gazed searchingly into green eyes, her voice small and oddly vulnerable. “Do you truly wish to have children? With me?”

Byleth nodded immediately, voice dripping with sincerity. “I want everything with you.”

Rhea breathed slowly, her eyes closing as she attempted to deal with the emotions suddenly threatening to overwhelm her.

“Perhaps not at this very moment,” Byleth added a moment later, suddenly remembering the work they still had ahead of them to stabilize Fódlan and help it prosper. “But someday.”

Rhea’s eyes blinked open, before she gazed down at Byleth. There was a sheen to her green orbs when she finally spoke, her whispered words infinitely soft and gentle. “Someday, dear one, I would like nothing more.”

**-+-+-**

**Author's Note:**

> So, I'm still in the process of writing the next chapter of This Time Between Us, and it might take a bit before I can post it. That being said, this has been sitting on my computer for a while, and since it was 90% complete, I decided to finish it up and post it in the meantime. I mean, some fluff is better than no fluff, right?
> 
> Also, thanks to Irock4691 over on FFN for giving it a look-over and some helpful input during the editing process.
> 
> EDIT: My logic here is that - whether it's through the power of her blood or her divine magic - if Sothis can have a bunch of dragon babies by herself, Byleth can have some with Rhea.


End file.
